I’m going in to the dentist to have the last of my teeth removed for dentures. Since I have a hip and a knee replacement, I’ll be on antibiotics to prevent infection. The dental surgeon explained to me that my joint replacements might get infected with this type of invasive surgery. But what I don’t understand is the connection between dental surgery and my joints. Why wouldn’t I just get a mouth infection?

As your dentist has explained, the practice of prescribing prophylactic (preventive) antibiotics for patients with joint replacements having dental work done is to avoid infection, which can have serious complications for anyone with a joint replacement.

Bacteria in the mouth can travel through the bloodstream and seems to have a preference for the joints. Once a joint with an implant is infected, serious damage and destruction can occur. Another surgery may be needed to clean the joint or even to remove and replace the implant.

Exactly why bacteria seems to target joints remains unknown. But there does seem to be a direct link between the gut and the joints. People with inflammatory bowel disease such as Crohn’s disease (regional enteritis) or ulcerative colitis, and anyone with “leaky gut syndrome” are at increased risk for joint problems.

There is some evidence that increased permeability (allows substances through easily) of the intestinal lining increases exposure to foreign substances. Bacteria is one of the things that seems to move out of the gut into the blood stream and heads for the joints. Joints that have been previously disrupted surgically may be at increased risk over other joints that haven’t been touched. But this has not been studied extensively or defined more clearly.